Automatic paper feeding unit



United States Patent [72] Inventor Wolfgang Hoffmann Beaconsfield,Quebec, Canada [21] Appl. No. 465,825

[22] Filed June 2, 1965 [45] Patented Aug. 18, 1970 [73] AssigneeCanadian International Paper Company Montreal, Quebec, Canada [54]AUTOMATIC PAPER FEEDING UNIT 2 Claims, 18 Drawing Figs.

[52] US. Cl 83/205, 83/210, 242/684 [51] Int. Cl B26d 5/20, B65h 75/02[50] Field ofSearch 156/351,

Primary Examiner John T. Goolkasain Assistant Examiner D. J. FritschAttorney Alan Swabey ABSTRACT: The machine for producing blanks of paperfrom a roll of paper is provided with two separate feeding means. Onefeeding means feeds the paper out ofthe machine. The second feedingmeans is operated by the feeding of the paper by the first means towithdraw more paper from the roll of paper. As the paper is fed out ofthe machine by the first feeding means, it is cut into required lengths.The first feeding means is driven selectively by a continuouslyoperating drive means. Further means can be provided on the machine forslitting the paper if required. Additiona1 means can also be providedfor applying a tear strip glued to the paper.

Pan tented Aug. 18, 1910 3,524,369

Sheet of7 al I INVENTOR Wolfgang HOFFMANN ATTORNEY Patented Aug. 18,1970 3,524,369

Sheet 2 of? INVENTOR Wolf an HOFFMANN ATTORNEY Patented Au 18, 1970'3,524,369

INVENTOR Wolfgang HOFFMANN ,4 TTORNEY Patented Aug. 18, 1970 3,524,369.

Sheet 4 of? INVENTOR Wolfgang HOFFMANN ATTORNEY Patented Aug. 18, 1970Sheet FIG.11

INVENTOR Fl 2 Wolfgang 'HOFFMANN IOO ATTORNEY Sheet 6 of? INVENTORWolfgang HUFFMANN ATTORNEY Patented Aug. 18,

Sheet FIGJS INVENTOR Wolfgang HQFFMANN ATTORNEY AUTOMATIC PAPER FEEDINGUNIT This invention relates to a web feeding mechanism.

In the packaging industry the mechanism employed for feeding thewrapping material to the packaging machine conventionally includes meansfor unwinding the material from a reel and shears for severing thematerial into blank lengths. The mechanism continuously performs itsoperating cycle and it is necessary to provide suitable devices forpreventing forward feed of the wrapping material until a blank isrequired by the packaging machine. This is a disadvantage in that such amachine requires components which have to be-specifically designed tocounteract the action of other components of the mechanism. A moreimportant disadvantage arises from the fact that, as the mechanismcycles continuously its components are wearing while in fact themechanism is merely cycling and is not performing any useful blankfeeding function. Such idle cycles may constitute up to 20% of theoperating cycles of the mechanism. The shears are particularly prone towear during idle cycles as the cutting edges rub on one another withoutan intervening layer of wrapping material which has a buffering effect.

In accordance with the present invention there is provided a mechanismfor supplying to a packaging machine a succession of blanks for wrappingpurposes. The wrapping material enters this mechanism in the form of anelongated web and is fed forward and cut into blank-lengths by the blankproducing mechanism. The means for feeding the web through the mechanismand the means for cutting the web into blanklengths are actuated insynchronism with one another.

Preferably, the blank producing mechanism operates cyclically andreceives its starts signal from the packaging machine itself when thepackaging machine is in a condition to receive a further blank. Thisstart signal gets in motion the means which feeds the web through themechanism and according to an advantageous embodiment the leading edgeof the advancing web is used to actuate a feeler member which thenproduces a signal indicating that measurement of a blank-length hascommenced. Operating the means which feeds the web for a short period oftime prior to beginning measurement of the blank length permits thefeeding means to obtain a uniform speed of web travel and thus providesmore accurate measurement of the blank length. A further detector, forexample an electric eye adapted to detect a printed spot on the web,brings the measuring cycle to an end and brings the feeding means to astop. This is virtually the end ofa single operating cycle except inthat the cutting mechanism then operates to sever a blank from theremainder of the web.

It will thus be understood that the mechanism which forms the subject ofthis invention does not have a fixed output rate but depends on theoutput ofthe packaging machine, that is to say, upon the frequency atwhich the start" signal is received. The advantage of this is that therecan be no pile-up of blanks should the product to be wrapped arrive atthe packaging machine at an irregular rate with, for example,considerable time intervals therebetween.

Having thus generally described the invention the same will now bedescribed in more detail with reference to the accompanying drawings, inwhich:

FIGURE 1 is a perspective view ofa packaging machine and in particularshows the web feeding mechanism;

FIGURE 2 is a front view illustrating the means for carrying a rolledweb of wrapping material;

FIGURE 3 is a horizontal cross-section through a fine adjustmentarrangement for the web roll; FIGURE 4 is a vertical section taken onthe line 4-4 of FIGURE 2;

FIGURE 5 is a view showing the supporting means for the shaft whichcarries the web roll, the view being taken on the line 5-5 of FIGURE 2;

FIGURE 6 is a vertical cross-section through a device for centering theweb roll on its supporting shaft;

FIGURE 7 is a vertical cross-section showing these components of thefeeding mechanism around which the web is entrained;

FIGURE 8 is a partial front view of the web-feeding mechanism andillustrates the specific arrangement for feeding a tear strip intojuxtaposition with the paper web;

FIGURE 9 is a vertical cross-section on the line 9-9 of FIGURE 8;

FIGURE 10 is a front view of the web feeding mechanism;

FIGURE 1 l is a rear elevation of a cutting arrangement for separatingthe web into blanks;

FIGURE 12 is a vertical cross-section through the cutting arrangement ofFIGURE 1 1;

FIGURE 13 is an elevation of the left-hand end of the machine (as viewedin FIGURE 10) and illustrates that part of the drive mechanism which isoutside the side frame of the machine;

FIGURE 14 is a diagrammatic view of the drive mechanism, and illustratesthat part of the drive mechanism which is within the machine side frame,FIGURE 14 being to a larger scale than FIGURE 13 and looking in theopposite direction;

FIGURE 15 is a front elevation ofa web slitting device;

FIGURE 16 is an end elevation of the web slitting device of FIGURE 15;

FIGURE 17 is a plan view of the web immediately prior to the web beingcut by the cutting arrangement of FIGURE 1 l; and

FIGURE I 8 is a perspective view of one wrapping blank cut from the web.

GENERAL ARRANGEMENT The web feeding mechanism described in detailhereinafter is adapted to supply, from a web of suitable material, aseries of wrapping blanks to a packaging machine of any suitable type.In FIGURE 1, the web feeding mechanism is designated PF and thepackaging machine proper, referenced PM and shown in phantom outline, ispreferably of the type disclosed in applicants copending United StatesContinuation-impart Application, Serial No. 416,929 filed December 8,1964, now Patent No. 3,354,600. The web feeding mechanism includes aframe 10 which serves to support a shaft 11 upon which the roll R ofpaper is mounted. To one side of the frame 10 is mounted a casing 12which contains the drive mechanism for the web feeding mechanism andalso a timing cam arrangement for actuating the various parts of the webfeeding mechanism in synchronism. Both the drive mechanism and thetiming cam arrangement will be described in more detail hereinafter. Atear strip feed device 13 is mounted on an overhead member 10A of theframe 10. This feed device is illustrated to a larger scale in FIGURES 8and 9 and will be described in more detail hereinafter.

PAPER ROLL SUPPORT ARRANGEMENT The roll R, as described, is supported onthe shaft 11, and the shaft 11 is supported at each end on a pair ofrollers 14 (see FIGURE 5). If desired a third roller can be providedabove and slightly to the left (as viewed in FIGURE 5) of the left-handroller. To facilitate positioning of the shaft 11, the part 103 of theframe 10 is made in the form ofa ramp up and down which the shaft portedon the rollers 14. To locate the roll R on the shaft two devices forlocating and centering the roll are provided. An example of a suitablecentering device is shown in detail in FIGURE 6. This device consists ofa cone-shaped member 15 which can be entered into the gap between theshaft 11 and the core 16 of the roll R thereby to center the core 16with respect to the shaft. The device further includes a substantiallycylindrical member 17 which is externally screw-threaded and which mateswith internal screw-threading of the member 15. A pair of holes 18 areprovided in the member 17 and a number of pairs of holes 19 are providedin the shaft 11. Pins, such as pin 20, can be pressed through alignedholes 18 and 19 to lock the member 17, and hence the member 16, againstaxial movement. To locate the roll R one centering device is pressedagainst the roll and locked into position by inserting a 11 can berolled from its position suppin through aligned holes 18 and 19. Theother centering device is then brought to a suitable location againstthe roll R and a further pin 20 placed in aligned holes 18 and 19. Oneof the members 15, or both of them, can be turned with respect to themember 17 whereby the member 15 is displaced axially along the shaft andpressed into contact with the core 16.

The position of the roll R transversely of the web feeding mechanismcan, of course, be coarsely adjusted by means of the centering devicesdescribed. However, to permit a fine adjustment of the position of theroll R a fine adjustment arrangement, generally indicated at 21, isprovided. The shaft 11 carries a pulley 22 having a deep annular groovein the periphery thereof. A small roller 23, mounted with its axisvertical, is positioned in the peripheral groove of the pulley 22. Theroller 23 is mounted on a block 24 which has two smooth rods 25 and ascrew-threaded rod 26 passed therethrough. The rod 26 meshes withcorresponding threading provided in the bore ofthe block 24. The rods 25are fixed to the frame 10 and the rod 26 is mounted on the frame 10 insuch manner as to be rotatable in its mountings. A handwheel 27 isprovided on the free end of the rod 26. By turning the handwheel 27 therod 26 is turned and the block 24, prevented from rotating by the rods25, is displaced along the rods 25 and 26. This in turn displaces theroller 23 which is thus urged against one annular surface of the pulley22. Consequently, the pulley 22 and the shaft 11 are urged axially sothat fine adjustments of the position of the shaft 11 can be made.

Also associated with the roll R is a friction strap 28 which carries aweight 29. The strap 28 while permitting material to be drawn from theroll R, prevents reverse rotation of the roll and also halts the rollsrotation immediately the force exerted on the web and tending to unwindthe web from the roll ceases.

WEB GUIDING COMPONENTS AND DRIVE MECHANISM The Web Was it is unwoundfrom the roll R is fed across an edge 30 (FIGURE 7) having a smallradius of curvature and formed on a member 31 extending transversely ofthe machine. The function of the member 31 is to eliminate, as far aspossible, the tendency of the web W, which obviously will have been inits rolled form for a considerable time, to return to its rolled formwhen relieved of any constraining action. The web W is then fed aroundtwo rollers 32 and 33, both of which are mounted in bearings fixed tothe frame 10, and then around a further roller 34 which is free to movein a vertical direction as will be described in more detail hereinafter.The roller 33 is driven as will be described. From the roller 34 the webpasses adjacent further rollers 35, 36 and 37. While passing around theroller 36 the web W and the tear strip are brought into engagement andwhile passing from the roller 36 to the roller 37 the web is slit by themechanism generally indicated at S. Subsequent to the slitting mechanism5 the web encounters, and is cut into lengths by, a cutting arrangementgenerally indicated at C.

The roller 33 co-operates with a number of driving discs 38 which aremounted on a rotatable shaft 39. The manner in which the shaft 39 isdriven will be described hereinafter. At each of its ends, the shaft 39is supported by a lever 40 (see also FIGURE 14) which is pivotallymounted at 41. A horizontal portion 42 of the lever 40 is formed as afork 42 and the shaft 39 is seated between the two prongs ofthe fork 42.

Each of the levers 40 is arranged to be oscillated by the roller 34about which the web is entraned. For this purpose, the roller 34 carriesadjacent each of its ends a ball bearing, the inner race of which isfast with the roller 34 and the outer race of which forms a rotatablecam. The roller 34 also carries a gear wheel 43 adjacent each of itsends and each gear wheel 43 co-operates with a vertical rack 44 securedto the frame 10 of the machine. Each lever 40 includes a track 45 uponwhich the outer race of the ball bearing, generally indicated at 46,runs. Vertical displacement ofthe roller 34 causes the lever 40 tooscillate from the full line position shown in FIGURE 14 to the positionshown in phantom lines in that figure. Suitable guides are provided forrestraining the roller 34 to travel in a vertical path.

The drive mechanism includes a main motor 47 (FIGURES IO, 13 and 14)which drives the web feeding mechanism via a chain 48 and reductiongearing 49. The output side of the reduction gearing drives a shaft 50and the shaft 50 has two chain wheels 51 and 52 thereon. Chains 53 and54 respectively are entrained around the chain wheels 51 and 52. Thechain 53 is entrained around a further chain wheel 55 which itselfismounted on a shaft 56. The shaft 56 is connected to the input memberofthe clutch ofa clutch and brake assembly generally indicated at 57.The output member of the clutch and brake assembly passes through theframe 10 and is referenced 58 (see FIGURE 14). This output member 58carries a gear 59 which meshes with a further gear 60. The gear 60 inturn meshes with a third gear 61 which is itself mounted on a shaft 62.The shaft 62 is mounted in bearings which are themselves carried byblocks 63 (one of which is illustrated in FIGURE 14 and the other ofwhich is at the opposite end of the shaft 62). The blocks 63 are mountedin vertical guides 64 and are spring-urged downwardly so that the gear61 is pressed into mesh with the gear 60. The shaft 62 carries aplurality of discs 65 (see FIGURES 7 and 10) which co-operate with theroller 37. The springs which urge the blocks 63 downwardly also serve tourge the discs 65 into engagement with the roller 37.

The chain 54 is entrained around a further chain wheel 66 which issecured to a shaft 67. The shaft 67 passes through the frame 10 andcarries a gear 68 which meshes with a gear 69 mounted on the shaft 33Aof the roller 33 (see FIGURE 7). A gear 69 meshes with a further gear 70which is mounted on the shaft 39. The bearings for the shaft 39 aremounted in blocks which are themselves in vertical guides generallyindicated at 71. The blocks are spring-urged towards the shaft 33. Thisarrangement is similar to the mounting of shaft 62.

The shaft 67 carries a further chain wheel 72 about which a chain 73 isentrained. The chain 73 transmits drive via a chain wheel 74 and aslipping clutch to a cam shaft 75.

A mechanism for locking the cam shaft 75 in a predetermined angularposition is provided, this locking mechanism consisting of an arm 76projecting from, and rotatable with, the cam shaft 75 and a pivotablymounted number 77. The member 77 is spring-urged to the position shownin FIGURE 13 in which its lower end lies in the path of rotation of thearm 76 mounted on the cam shaft 75. An air cylinder 80 is pro videdwhich, when supplied with air, forces a plunger 81 against the pivotablymounted member 77 so as to rotate this member and displace its lower endout of the path of travel of the arm mounted on the cam shaft, therebyto free the cam shaft. Air is applied to the cylinder 80 by a valve 82the control ofwhich will be described hereinafter.

CUTTING MECHANISM A cutting mechanism, generally referenced C in FIGURE7, is provided for severing the web W into blanks of the desired length.The cutting mechanism includes a vertically displaceable cutter (seeFIGURES l l and 12) and a fixed cutter 91. The cutter 90 has a cuttingedge in the form of a shallow, inverted V and the cutter 91 has astraight, horizontal cutting edge. The cutters 90 and 91 are fixed onstrengthening boxsection members 90A and 91. At one end the member 90Ais secured, for example by welding, to a bush 92 which is adapted toslide on a shaft 93. The other end of the member 90A moves in a verticalslideway 908 and the member 91A is fixed to the frame 10 at each end.The member 90A is adapted to be displaced vertically by a linkageincluding a pair of rods 97 and a pair of levers 98, one of which hastwo arms and the other of which has three arms. The levers 98 arepivotally mounted on a frame structure generally indicated at 99. A tierod 100 joins other arms of the levers 98. The lever 98 including thethird, longer arm 101 has that arm connected to a plunger 102 of an aircylinder 103 which itself is pivotally mounted on a bracket 104 securedto the frame of the machine. The mounting of the cutter 90 includessprings 90B permitting restrained sideways movement of the cutter 90with respect to the cutter 91 to permit the cutters to move one past theother.

SLITTING ARRANGEMENT As will be seen from FIGURES l5 and 16 thepaperslitting arrangement includes an inverted channel-shaped support110 the depending arms of which rotatably support a transverse crossmember 111 which is the form of a shaft. At one end of the shaft thereis fixedly secured a collar 112 which is integral with a lever 113. Aplunger 114 of an air cylinder 115 is connected to the lever 113 andserves to oscillate the lever 113 and hence to rotate the collar 112 andshaft 111. The air cylinder 115 is pivotally supported upon a bracket116 depending from the frame part 10A. Also rigidly secured to the shaft111 is a further collar 117 from which extends an arm 118, having apaper slitting blade 119 at the free end thereof. Towards its right-handend (as viewed in FIGURE the shaft 111 carries a sleeve 120 which isfree to rotate about the shaft 111. The sleeve 120 carries fasttherewith a collar arrangement generally indicated at 121 from whichextends two arms carrying two parallel blades 122 and 123. An aircylinder generally indicated at 124 is connected to the sleeve 120 inthe same manner as the air cylinder 115 is connected to the collar 112.The air cylinder 124 serves to rotate the sleeve 120 about the shaft111. The cylinders 115 and 124 could be replaced by solenoid operatedplungers or mechanical means such as cam devices.

The cylinder 115 is, in FIGURE 16, shown in its operative condition inwhich the arms 113 and 118 have been rotated with the shaft 111 in ananti-clockwise direction to bring the blade 119 into engagement with theweb for slitting purposes. Air is supplied to the cylinder 115 from asuitable source (not shown) and includes within itself return springmeans for returning the plunger 114 to its retracted position andconsequently lifting the blade 119 away from the web immediately supplyofair to the cylinder ceases. The blades 122 and 123 are actuated in asimilar manner by the air cylinder 124.

TEAR STRIP FEEDING ARRANGEMENT The arrangement for feeding a tear stripinto contact with the web W is illustrated in detail in FIGURES 8 and 9,and, as described above, has the general reference numeral 13 appliedthereto. The arrangement 13 includes a bracket 130, in the form of anupright channel section. mounted on the frame part 10A. A rotatableshaft 131 isjounalled in the bracket 130 and extends transversely ofthepaper feeding mechanism. The shaft 131 serves to support a reel 132 uponwhich the tear strip is wound. The tear strip is indicated by thereference T. The device for 13 further includes a frame part, generallyindicated at 133, which depends from the bracket 130 and, for example,may be welded thereto. The frame part 133 serves to support a gluingarrangement generally indicated at 134 which serves to apply adhesive tothe web W along a thin, strip-like zone ofthe web W. The gluingarrangement 134 can be ofany suitable known form and its operation willbe described in more detail hereinafter.

A short rod 135 projects forwardly from the bracket 130 and carries aknurled knob 136 on the free end thereof. The end portion of the rod 135is screw-threaded and the knob 136 has corresponding internal threadingwhereby the knob 136 may be displaced along the non-rotatable rod 135.The rod 135 passes freely through an arm 137 and spring 138 is disposedbetween the arm 137 and the knob 136.

A stub shaft 139 extends transversely of the bracket 130 and parallel tothe shaft 131. The stub shaft 139 is suitably journall ed in the framepart 133 and carries a roller 139A having a deep peripheral groovetherein. The tear strip T is seated in this groove and the roller 139Aserves to guide the tear strip so that it contacts the web W at thecorrect transverse locatron.

The arm 137 is fast with an arm 140 upon which a roller 141 is mounted.The spring 138 acts through the arms 137 and 140 urges the roller 141downwardly against the tear strip T and squeezes the tear tape T and theweb W between itself and the roller 36. The stub shaft .139 passesthrough the arm 140 and acts as a pivot for the lever constituted by thearms 137 and 140.

CAM ARRANGEMENT The various parts of the feeding mechanism are operatedsynchronously by means of five cams which are mounted on the cam shaft75. The operation of these cams will be described hereinafter in detailwhen the operation of the described paper feeding mechanism isexplained. Stated briefly, the cams have the following functions.

Cam 1 is used to measure the length of the web and at the same timeresets the electric eye circuit when printed material is used.

Cams 2 and 3 respectively control supply of air to the air cylinders 115and 124. Consequently, these cams control the length of time that theblades 119, 122 and 123 are pressed downwardly and hence determine thelength and position of the slits which are made in the web W.

Cam 4 operates the gluing mechanism 134. For example, the gluingmechanism 134 can be of the type in which there is a reservoir of glueand an air inlet to the reservoir to pressurize the same and expel gluethrough a nozzle. Consequently, the cam 4 determines the periods duringwhich glue is supplied by the giving arrangement 134.

Cam 5 controls supply of air to the air cylinder 103 and consequentlycontrols the cutter mechanism C.

MISCELLANEOUS CONTROLS The feeding mechanism includes a feeler fordetecting passage of the leading edge of the web past a certain point.This feeler is located to the left of the cutter mechanism (as viewed inFIGURE 7). Furthermore, the paper feeding mechanism includes aphoto-electric eye (not illustrated) for detecting the passage of-spots" printed on the web W. This eye is associated both with cam 1 andwith the clutch and brake assembly 57 as will be described hereinafter.

Before undertaking an explanation of the manner in which the paperfeeding mechanism operates it should first be mentioned that the signalwhich initiates each cycle of the paper feed mechanism emanates from thepackaging machine PM. That is to say, when the packaging machine PM canaccept another sheet or blank of wrapping material a signal istransmitted to the clutch and brake assembly 57. For example, a suitablemicroswitch or other detector can be provided in the packaging machineto detect passage oftlte previous wrapping blank pasta particularlocation in the packaging machine.

OPERATION OF THE FEEDING MECHANISM As mentioned immediately above thepaper feeding mechanism operates cyclically and the signal setting thecycle in operation is received from the packaging machine when thepackagaing machine is in a condition to receive a further wrappingblank.

During operation of the feeding mechanism, the motor 47 operatescontinuously. Consequently, the input member of the clutch assembly 57,the gears 68, 69 and 70 and hence the roller 33 and shaft 39 and theinput member of the slipping clutch on the cam shaft all rotatecontinuously.

The signal from the packaging machine PM is received by the clutch andthe brake assembly 57 and immediately releases thebrake and engages theclutch so that drive is transmitted through the shaft 58 to the gears59, 60 and 61. Consequently, the roller 37 and the shaft 62 are rotatedand the paper web is fed in the direction of the arrow A. (seeparticularly FIGURE 7). To enable the desired length of paper web to befed to the packaging machine, the feeler I50 described above is providedin the path of travel of the web W to detect passage of the leading edgeof the web. It will be understood that at the moment that the clutch andbrake assembly 57 are actuated, the leading edge of the paper web is atthe cutting mechanism C, that is, at the location at which the previousblank was severed from the remainder of the web. Locating the feeler 150spaced from the cutter allows the feeding means to have the web runningat uniform speed by the time blank measurement is to begin. If blankmeasurement were to begin at the same instant that clutch 57 wasengaged, it is possible that the blank measure would not be the same ineach case due to inherent play in the mechanical web drive means. Thedistance the feeler 150 is spaced from the cutter must be sufficient tobegin measurement when the web is being fed at uniform speed. The signalfrom this feeler denoting passage of the web W is fed to the valve 82which is than actuated to connect a source of compressed air (not shown)to the air cylinder 80. The plunger 81 is then thrust to the right asviewed in FIGURE 13, and rotates the arm 77 clockwise about itsmounting. The arm 76 on the cam shaft 75 is thus released so that driveto the slipping clutch becomes effective to rotate the cam shaft 75.Immediately thereafter the arm 77 returns to its initial position sothat it will arrest the cam shaft 75 after the cam shaft has completed asingle rotation.

Immediately the cam shaft commences to rotate, the supply of air to thegluing mechanism 134 is commenced so that glue feeds onto the web W. Inother words, cam 4 becomes effective to open the air supply to themechanism 134. During the previous cycle, a length of the strip T hadbeen glued in the desired manner to the web W over that length of theweb which lies between the mechanism C and the roller 36. The movementof the sheet located between roller 36 and cutter mechanism C, havingthe tear strip glued thereon, outwardly to the packaging machine resultsin an additional length of tear strip T being pulled from the reel 132.The strip is guided by the roller 139 into engagement with theadhesive-coated strip-like zone of the web W, the strip being pressedinto engagement therewith by the spring-loaded roller 141, so that theweb and tear strip are firmly adhered together.

At suitable times during the cycle the cams 2 and 3 open the valvescontrolled thereby so that air is fed to the air cylinders 115 and 124with the result that the blades 119, 122 and 123 are urged downwardlyand slit the paper. If reference is made to FIGURE 17 it will be seenthat the blades 122 and 123 produce short slits 150 and the blade 119produces a longer slit 151. In other words, the air supply to thecylinder 115 continues for a longer period of time than does the airsupply to the cylinder 124.

The pull on the web as it is fed forward by the roller 37 and the discs65 is insufficient to overcome the resistance that the strap 28 andweight 29 impart to the roll R. Consequently, the length of web betweenthe roll R and the roller 37 shortens and this in turn has the effectoflifting the roller 34, the movement ofthe roller 34 being ofsufficient stroke to make available witho'ut rotating the roll R alength of web greater than that which is to be fed past the cuttermechanism C. As the roller 34 rises it acts as a cam, permitting thelever 40 to rotate in a clockwise direction (as viewed in FIGURE 7)about its pivot point 41. As the roller 34 reaches the top part ofitsvertical travel the lever 40 pivots sufficiently far about its pivotpoint 41 to bring the discs 38 into engagement with the web and to gripthe web between the discs 38 and the roller 33. As mentioned, the roller33 and shaft 39 are rotated continuously and the roller 33 and the discs38 slip on the web W until such time as the discs 38 grip the webbetween themselves and the roller 33. These components then serve tofeed a length ofthe web W from the roll R, and as the length of webbetween the roll R and the cutter C increases the roller 34 descendsonce more. As the roller 34 reaches the bottom part of its travel theroller 33 and the discs 38 move out of engagement so that the webfeeding mechanism constituted by these components ceases to operate.

The spots" printed on the web are spaced apart in dependance on thedesired length of the blank which is to be cut from the web. Thephoto-electric eye described above is actuated immediately one of thesespots comes into co-operating relationship with the eye. The signal thenproduced by the electric eye is fed to the clutch and brake assembly 57to release the clutch and engage the brake so that drive of the paperweb immediately ceases, the roller 37 and shaft 62 being brought to analmost instantaneous stop.

To insure that the photo-electric eye does not transmit a signal toclutch and brake assembly 57 prematurely, for example, because of a darkcolored mark or other blemish on the web, the cam 1 serves to "activatethe eye shortly before the spot on the web W reaches a position in whichit cooperates with the eye. This minimizes the chances ofimproper andpremature engagement of the brake and disengagement of the clutch. Thecam 1, after the clutch and brake assembly has been actuated, thenrenders the eye inoperative until late in the next cycle. It will beapparent that the electric eye can be located in any convenient positionprior to and adjacent the cutting means.

The final stage in the cycle is the actuation of the cutting mechanism Cby the fifth cam, this cam serving to open the valve which supplies airto the air cylinder 103 thereby to bring the top cutter downwardlybeyond the lower cutter 91. In view of the shape of these two cuttersthe cutting action thereof is substantially that of scissors, the blankbeing cut inwardly from each edge towards the center as the cutters 90and 91 progressively overlap.

As will be seen from FIGURES l7 and 18 the cutters 90 and 91 sever theblank transversely of the web through the slits and 151. The blank, onceseparated from the remainder of the web, is drawn into the packagingmachine by a feed arrangement forming part ofthe packaging machine.

The slits 150 facilitate folding of the blank around the package to bewrapped, and the slits 151 permit the edge of the blank, once wrappedaround the package, to be raised slightly so that firm grip may be hadon the blank at one or other of the zones Z (FIGURE 18). By pulling onthe strip T the package may be opened readily.

The above described operation can be summarized as follows:

(1) Signal received at assembly 57 to commence feed of web past cuttermechanism C.

(2) After a short distance of web travel, feeler 150, located in thepath of travel of the web from the cutter, detects the leading edge ofthe web and transmits signal to valve 82 to free cam shaft 75 forrotation.

(3) Cam 4 actuates the glue mechanism 134.

(4) Cams 2 and 3 actuate slitting mechanism.

(5) Roller 34 rises to set in motion the web feed components whichwithdraw the web from the roll.

(6) Electric eye is activated" by cam 1 and detects spot to disengageclutch and engage brake ofassembly 57.

(7) Glue mechanism ceases to operate.

(8) Roller 34 descends and the web ceases to unreel.

(9) Cutter mechanism is actuated by cam 5.

(10) Eye is deactivated by cam 1.

With a view to speeding up the operation of the paper feeding mechanismit is possible to employ air clamps for urging the shaft 39 towards theshaft 33 rather than to use the motion of the roller 34 for thispurpose. This avoids the delay which normally occurs between the timethat the roller 34 begins to move upwardly and the time that the discs38 engage the web.

I claim:

1. A mechanism for producing wrapping blanks from a roll of sheetmaterial comprising first means for feeding a length of material. secondmeans located between the first means and the roll of inaterial actuatedby the feeding of the first length of material for withdrawing a furtherlength of material from the roll, a continuously operative drive means,means for selectively connecting the drive means to said first feedingmeans to control operation of the first feeding means, and

means for cutting the material fed by the first feeding means intoblanks after the first feeding means is disconnected from the drivemeans; the means for actuating the second feed means including a rollermounted to move vertically, the roller being moved vertically throughthe feeding of the sheet material through the first feeding means, theroller bearing against a pivotable cam lever during its movement, theroller causing the lever to pivot after having moved a predetermineddistance to initiate operation of the second feeding means.

2. In a mechanism for delivering a succession of relatively shortwrapping blanks produced from a relatively long web of wrapping materialwound onto a central core to form a roll, means for supporting said rollcomprising a mounting shaft,

the mounting shaft being adapted to pass through said core, means forcentering said core with respect to said shaft, means for locking saidroll in position on said shaft to prevent movement thereof along saidshaft, and means for permitting fine adjustment of the position of saidshaft in the direction of its axis; the centering and locking meanscomprising a pair of two-part members, one part of each member being ofconical form displaceable along said shaft and adapted partly to entersaid core thereby to center said core. and the other part of each memberbeing adapted to receive an element for fixedly securing said other partto said shaft, and said one and other members being connected to oneanother by screw-threading.

